The House of Hades is the longest book in the Heroes of Olympus series (possibly also the longest book Riordan has ever written?) and also one with pivotal and complex events taking place. As such I went into it suspecting that the adaptation to a graphic novel may not have been as easy as some of Riordan's other books. On the whole, I think Robert Venditti did a good job but it definitely didn't feel as strong a read as the novel and there are parts where readers new to the story may not fully understand what is happening. 

The art is generally well done, with a few panels I particularly loved; however it does suffer from having too many panels that are extremely busy. (I do appreciate why as there are plenty of battle scenes as well scenes in Tartarus full of monsters). I did find some of the dialogue hard to read as speech bubbles were presented in different colours and sometimes lacked enough contrast. 

Overall I had a good time and I really enjoy having these graphic novel adaptations - I hope after Blood of Olympus they go on to do more Riordan books.